Russell Johnson, the actor known as the quirky, smart Gilligan's Island character, the Professor, has died at age 89.

ABC News confirmed with the actor's wife, Constance, that Johnson died Thursday morning of kidney failure.

"He
died at home, peaceful, in his sleep at 5:21 am today," she said. "[He
was] a very brave guy who knew what he wanted, and he wanted to be at
home."

Originally from northeastern Pennsylvania, Johnson served in World War II
before pursuing an acting career. He acted in several TV programs in
the 1950s and '60s, including "The Adventures of Superman," "Alfred Hitchcock Presents" and "The Twilight Zone." However, his most famous role came along in 1964: The Professor on "Gilligan's Island."

Johnson, a Washington resident, leaves behind his wife and a daughter, Kim.